Field-hardened optical waveguide hybrid integrated-circuit multisensor chemical probe and its chemistry

A single probe containing three hybrid integrated-circuit, optical waveguide, chemical-biochemical sensors (chip sensors) has been developed. Each chip sensor contains two hybrid waveguides -- one for sensing and one for reference. The sense waveguide is coated with a species-specific or group-specific chemistry or biochemistry. The reference waveguide is coated with a version of the sense chemistry or biochemistry, which is not sensitive to the analyte. The integrated structure is encapsulated and contains a single fixed light source, two detectors (reference and sense), and an optical train. The design is amenable to fluorescence, absorption, and refraction measurements. The three chip sensors are individually mounted in a probe that contains all of the electronics and computing capability necessary to collect and process the output information from each chip sensor. Only the surface of the individual chips are exposed to the target analytes. The probe is rugged, intrinsically safe, and can operate under 75 m (250 ft) of water.